[Nexus 7 (2013) Q&A] paranormal11:
Hi k23m, thanks for fast reply, i usually don't sit waiting for a reply, While i waiting some reply i found something really interesting...

GUIDE/INFO ABOUT CORRECT DIAG CONNECTION NEXUS 7 useful to work with QPST(for example BACKUP / RESTORE QCN).

Don't ask why i can believe that with LG DIAG drivers works, but this is the truth, the idea born seeing a japanese site that to enable a special BAND on the phone, working on QCN file, must connect corectly Nexus 7 in diag mode before any operations.

The others thing that make me believe it's possible is because the Bootloader of the Nexus 4-5-5x phones made by LG in the specifically periods near when Nexus 7 is launched, i remember that LG Bootloader look like really similar or equal to an Asus Nexus 7 Bootloader.

Remeber the spirit of this community, collect info->study->try->post result

Because when i want something i try all i can, yesterday i try to backup a QCN from a working (with correct IMEI) Nexus 7 using the LG Driver for the port DIAG MODE instead of Qualcomm, and after some trying i succesfully made it.

Requirements:

Device Rooted

Bootloader Unlocked

Install correct LG Diag Driver

https://androidfilehost.com/?fid=95916177934521832

QPST 2.7.460

Enable Debug USB on Nexus 7 2013

Enable DIAG mode on Nexus 7 2013

(To enable diag mode you can do it using minimal adb and fastboot, connect Nexus 7 with Debug USB active, check connection with

(<- mean push Enter)

ADB DEVICES <-

then enable diag mode with

ADB SHELL <-

su <-

setprop sys.usb.config diag <-

Now the nexus 7 will disconnect and reconnect in diag mode, and the Diag drivers will be installed, when done check that the correct drive is installed (correct drivers name is listed below)***

***If you have connection problem to backup QCN, try enable diag mode on the Nexus 7 with terminal emulator. Open the terminal and give

su <-

setprop sys.usb.config diag <-

If you try with QPST Configurator -> Service Download->Backup QCN there's no way that works, with Qualcomm drivers USE ONLY the LG DIAG driver

If you load the Qualcomm diag drivers or wrong drivers, in QPST configurator in the Ports tab under Phone section the Nexus APPARENTLY connected in diag mode is know as APQ8064 (seems correct because the cpu inside Nexus 7 is APQ8064 but in this way no correct diag connection and it's not possible to backup restore QCN, because the tablet is not correctly connected in diag mode)

If you load the correct LG diag drivers , when you open QPST configurator can't found the Phone/Ports automatically, you have to do manually:

Under Ports tab click on

Add New Ports

and under Serial/USB Ports tab in the field Port:

write your n°COM ports(for example COM17) that under device manager on your PC is called LGE AndroidNet For Diagnostics Port (COM.here is your Port number.)

Then click OK to add the Ports, now you can realize that the Nexus 7 is now known as SURF9615 and the DIAG connection works correctly, and it's possible to backup restore QCN, because the tablet is correct connected in diag mode.

The others way to backup QCN on Nexus 7 is using QFIL (inside QPST package)->Tools->QCN Backup Restore

Naturally you have to install LG DIAG driver, under device manager the port name must be:

ADB Interface

-AndroidNet Sooner Single ADB Interface

Modem

LGE AndroidNet USB Modem Port

Ports

-LGE AndroidNet For Diagnostics Port

-LGE AndroidNet USB Serial Port

Remember to reboot PC when installing new drivers, and reboot Nexus 7 to make a stable connection and to avoid temporary drivers misbeahve that result in a non correct connection, even if all is in order and seems ok

With a correct diag connection i finally i use WriteDualIMEI(W+G_eMMC) to rewrite an example IMEI of 123456789012345 and after a power off/power on the IMEI from 0 change to 123456789012345 and till now all ok.

Now i can hear your laughling, because when i try to change the IMEI for the second time to insert the correct one, after write correctly with WriteDualIMEI(W+G_eMMC) after a power off/power on i found the 123456789012345 IMEI is not changed, i tried 2-3 times but the IMEI won't change anymore.

Now here's the Question for k23m or anyone

Now i think to remember that when you change IMEI is best/need to wipe the partition where IMEI is stored, to effective IMEI changing, sometimes is best to reprogram starting with 0 IMEI?

I ask you more info about that. Must i delete some mccblk or reflash? Please explain me how is the correct procedure order, hoping that my DIAG USB CONNECTION GUIDE will be useful for others users.

REGARDS TO ALL THE COMMUNITY

THIS THREAD REFLECT THE SPIRIT OF XDA COMMUNITY